Emphasizing either legs OR boobs, not both, is a style rule that I live by (and one Blake Lively should pay more attention to). If you're going low cut, or short, it's always best to let one of your assets be the focus. And, for the most part, I pick legs.
Being on the more petite end of the spectrum (I like to think I am 5'5", but that may or may not be a slight embellishment), I love any shoe that makes my legs resemble those of a glamazon, like Elle MacPherson.
While supermodel stature is out of bounds, I do think I've found a stylish solution: ankle strap shoes. Whether on heels, flats, sandals, platforms or flatforms, this small detail makes any pair of shoes slightly more flattering. Why, would that be? A strap draws attention to the ankle, which is typically the thinnest part of the leg. And thinner = longer in this equation.